Royal Gunpowder Mills in Ballincollig date from 1794 when Charles Henry Leslie built the first mill along the bank of the River Lee. During the Napoleonic Wars eleven years later, the British Board of Ordnance purchased the mills and vastly increased their size. An Army barracks was built alongside to protect the mills. These barracks now called Murphy Barracks are occupied by the Irish Army.

When the war ended in 1815 the demand for gunpowder declined and it wasn't until the 1830's when a Liverpool company bought the mills that the final and biggest expansion took place. By the mid 1850's over 500 people were employed and the mills supplied black gunpowder all over the British Empire. By the turn of the century cordite was rapidly replacing gunpowder and the mills finally closed in 1903.

Today the mills provide a unique insight into life during the nineteenth century and are a place of great interest to both locals and visitors.